👥 Users Service – NestJS + Redis + Prisma

A scalable and high-performance user service built with NestJS, Prisma, and Redis-based versioned caching.

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🚀 Features

• 🔧 Clean architecture with Repository & Service layers
• ⚡ High-speed Redis caching with version control
• 🧪 Easy to test and extend
• 📦 Built with Prisma ORM and TypeScript
• 🛡️ Type-safe DTOs and clean code structure

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✅ API Endpoints

Method	Endpoint	Description
GET	/users	Get all users
GET	/users/:id	Get user by ID
POST	/users	Create a new user
PUT	/users/:id	Update existing user
DELETE	/users/:id	Delete user

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🧠 Redis Caching Strategy

This service uses versioned Redis caching to ensure high performance and consistency, without manual cache invalidation.

🔄 Versioned Cache Keys

• List cache key: users-v:{version}
• Single user cache key: user:{id}-v:{version}

🔧 Versioning Logic

• GET /users → Reads from users-v:{version}
• POST /users → Creates user, then INCR users:version
• PUT /users/:id → Updates user, bumps users:version and user:{id}:version
• DELETE /users/:id → Deletes user, bumps versions

This ensures that any mutation (create/update/delete) results in a new cache version, without needing to delete keys.

⏳ Expiration

Cached data is automatically set with an expiration time (e.g., 1 hour), keeping memory usage optimized.

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🧪 Testing the Cache

# 1. Initial request - DB hit + cache set
GET /users

# 2. Create user - version incremented
POST /users

# 3. Request again - new version forces DB hit and new cache set
GET /users

# 4. Same logic applies for:
GET /users/:id
PUT /users/:id
DELETE /users/:id